frankv3,
1. "even after registering it manually at the command line with "C:\Program Files\Common Files\ArcGIS\bin\EsriRegasm" there is no tlb file even though it reported back that it was registered successfully"
= Registering the custom component DLL file manually with ESRIRegAsm at a command line achieves the task of actually registering the custom component. It does not produce the TLB file that you are looking for. I use that approach as an alternative to the Customize dialog/TLB file approach. Also, as far as I know, you do not need the TLB to be produced in order to invoke ESRIRegAsm. In fact, I just quickly tested this assumption by deleting my TLB before registering a .NET DLL with ESRIRegAsm, and my custom tool registered successfully.
2. "[ESRIRegAsm at the command line] reported back that it was registered successfully"
= It sounds like the custom command (ViperPin tool) has registered successfully. Does it not appear as a command in the category specified in the code (Developer Samples category)? It may already be registered and ready to be dragged onto a toolbar.
3. The Register for COM Interop is a checkbox in the following location:
Right-click on project in the Solution Explorer > Properties option > Compile (or Build) tab.
You should see the checkbox. I believe an express version of either VS2008 or VS2010 should have that checkbox in that location. However, it should already be checked for the ViperPin tool project. It would only be unchecked if you unchecked it yourself.